Matrix‐producing cells formed ‘Van Gogh bundles’ facilitate Bacillus subtilis biofilm self‐healing

Abstract

Biofilms grow and expand through cell differentiation into various phenotypes, which have different functions and cooperate with each other. In our experiments, we find that biofilms can heal after damaged, and we also find there is a special structure near the cut, which is called the 'Van Gogh bundles' by Jordi et al. because of its resemblance to Van Gogh's famous painting 'The Starry Night'. Here, we study the 'Van Gogh bundles' structure evolution near the cut area, and how 'Van Gogh bundles' structure facilitates the cut healing by observing microscopic images of bacterial colonies growing from wild-type and mutant strains. We find that the amount of matrix-producing cells contributes to the 'Van Gogh bundles' structure, such as curvature. Through the comparison of curvatures of 'Van Gogh bundles' and the rate of the cut healing, we find that the smaller the curvature, the faster healing rate. To better explain the above experiment observations, we establish an individual-based model and simulate the formation and growth of 'Van Gogh bundles' along the cut by giving rules for an individual cell like cell growth, division and turning rules, and also 'Van Gogh bundles' fold division rule.

Residual cells and nutrient availability guide wound healing in bacterial biofilms

“…48 While everyday laboratory practice suggests that biofilms are capable of regeneration after a mechanical damage, systematic studies of this process are very limited. 49–51 Considering that biofilm-forming B. subtilis bacterial colonies growing on agar substrates, it has been studied how the colonies recover after cuts of different geometries, different ages of a wild type biofilm and several matrix mutants. 49–51…”

“…49–51 Considering that biofilm-forming B. subtilis bacterial colonies growing on agar substrates, it has been studied how the colonies recover after cuts of different geometries, different ages of a wild type biofilm and several matrix mutants. 49–51…”

“…48 While everyday laboratory practice suggests that biofilms are capable of regeneration after a mechanical damage, systematic studies of this process are very limited. [49][50][51] Considering that biofilm-forming B. subtilis bacterial colonies growing on agar substrates, it has been studied how the colonies recover after cuts of different geometries, different ages of a wild type biofilm and several matrix mutants. [49][50][51] In this work, we propose a combination of experiment and whole-biofilm lattice-based simulations to investigate the dynamics of wound healing in bacterial colonies grown on an agar substrate.…”

“…[49][50][51] Considering that biofilm-forming B. subtilis bacterial colonies growing on agar substrates, it has been studied how the colonies recover after cuts of different geometries, different ages of a wild type biofilm and several matrix mutants. [49][50][51] In this work, we propose a combination of experiment and whole-biofilm lattice-based simulations to investigate the dynamics of wound healing in bacterial colonies grown on an agar substrate. Here we specifically focus on the large scale dynamics of biomass, effects of cell physiological state and nutrient gradients.…”